The present invention relates to structures having a rod-like lateral cross section of the type often found in vehicles such as cars, buses, trains, airplanes and the like. Examples would include the steering wheel in an automobile and a handrail in a bus, railroad car or airplane.
Usually, such structures comprise a steel rod or tube. Sometimes, the steel rod or tube is encased in a soft covering of a material such as polyvinyl chloride to give the member a soft feeling. Either way, the structural member is dangerous in the event of an accident. As a practical matter, the covering cannot be made sufficiently thick to prevent serious injury in the event an individual impacts the hand rail, steering wheel or the like.
For this reason, some prior artisans have developed steering wheel columns which are collapsible on impact. When the steering wheel is impacted during an accident, the entire steering column tends to collapse and thereby absorb the energy of impact. Such a structure is costly and is not particularly applicable in other objects of rod-like cross sections found in vehicles such as hand rails or the like.